1. Field of the Invention
The present invention generally relates to an elevated refractory alloy with ambient-temperature and low-temperature ductility and a method thereof, more particularly, at least four high-melting point metal elements are composed with at least four carbides of the high-melting point metal elements through a high-temperature alloy process so as to produce the elevated refractory alloy with ambient-temperature and low-temperature ductility.
2. Description of the Prior Art
Nowadays, US Air Force Lab has developed high intensity alloy that has tungsten (chemical symbol is W, melting point is 3380° C.), tantalum (chemical symbol is Ta, melting point is 2996° C.), molybdenum (chemical symbol is Mo, melting point is 2620° C.), niobium (chemical symbol is Nb, melting point is 2468° C.), and vanadium (chemical symbol is V, melting point is 1730° C.) and is categorized into two parts, body-centered cubic structure with 4-element W—Nb—Mo—Ta and body-centered cubic structure with 5-element W—Nb—Mo—Ta—V. (please refer to attachment 1, Refractory high-entropy alloys, Intermetallics 18 (2010) 1758-1765)
Such elements as tungsten (chemical symbol is W, melting point is 3380° C.), tantalum (chemical symbol is Ta, melting point is 2996° C.), molybdenum (chemical symbol is Mo, melting point is 2620° C.), niobium (chemical symbol is Nb, melting point is 2468° C.), rhenium (chemical symbol is Re, melting point is 3180° C.) and vanadium (chemical symbol is V, melting point is 1730° C.) are body-centered cubic structures except rhenium under ambient-temperature, wherein rhenium is a hexagonal to closed-packed structure (HCP).
The crystallographic structures of aforesaid elements are characterized in that of high-temperature resistance, high ductile-to brittle transition temperature, as an example, tungsten reaches over 300° C. Hence, the elements are very intensive under ambient-temperature so as to hardly be rolled, forged, plastic-deformed, working-deformed, etc. Even though US Air Force Lab has developed such high intensity alloy, the disadvantages of the alloy are body-centered cubic structure, not ductile under low-temperature, so that manufacturers for alloy products are inconvenient.
Further, other information to the high-temperature resistant alloys are as below:    1. Issue No. TW I279445 and Publication No. US 20080257107 provide hardmetal compositions, which include hard particles having a first material and a binder matrix having a second, different material comprising rhenium or a Ni-based superalloy. A two-step sintering process may be used to fabricate such hardmetals at relatively low sintering temperatures in the solid-state phase to produce substantially fully-densified hardmetals. However, the two cited prior arts, TW I279445 and US 20080257107, produce the hardmetals that are to increase the strength and intensity, so that the means thereof is totally different than the present invention.    2. Issue No. TW I298657 provides a method for manufacturing metallic glass matrix composition material. Firstly, a high power ball mill machine is used to process a process of mechanical alloying. That is, metallic glass matrix composition powder and milling tanks are disposed in a vibration ball mill machine, a planet ball mill machine, or a stirring ball mill machine so as to produce the metallic glass matrix composition material powder that has a super cool liquid region, which is defined by a temperature difference of a glass transition temperature and a crystallization temperature. The metallic glass matrix composition material powder with the super cool liquid region is thus disposed in a thermoforming device and heated up to and kept in the temperature scope of the super cool liquid region. Within the period of keeping temperature, to continuously compress the powder is to increase the porosity the embryonic body of the powder, so that the bulk of the metallic glass matrix composition material is gained, and the bulk is composed by amorphous matrix composites and carbide strengthening. However, the cited prior art, TW I298657, adopts the amorphous matrix composition material that is a random internal atomic arrangement or not including crystallographic structures, hence the present invention is totally different than the cited prior art.    3. Issue No. CN 1490423A, a method for manufacturing tungsten carbide base that is high-temperature and adhesive resistant, adopts bonding phase powder master alloy, and Co-base wrought superalloy is the base of the bonding phase powder master alloy and includes the elements of cobalt (Co), Chromium (Cr), Nickel (Ni), tungsten (W), aluminum (Al), etc., elements damaging the performances of hardmetal alloys shall be eliminated and elements urging an oxide adhesion layer on the surface of the alloy within the process of machining the hardmetal alloy are added into. However, the means and purposes of the cited prior art, CN 1490423A, are completely different than the present invention.    4. Issue No. U.S. Pat. No. 4,066,451 is talking about carbide compositions for wear-resistant facings, which are consisted of fine-grained and hard two-phase mixtures of subcarbide, (Mo,W).sub.2 C, and hexagonal monocarbide (Mo,W)C, and solid solutions, and are formed by solid state decomposition of the pseudocubic. On the other hand, the present invention adopts a high-temperature process of composing high-melting point metal elements and carbides corresponding to the high-melting point metal elements. However, the means and purposes of the cited prior art, U.S. Pat. No. 4,066,451, are completely different than the present invention.
Accordingly, to provide an elevated refractory alloy with ambient-temperature and low-temperature ductility and a method thereof may be a best solution.